Thread control mechanism for sewing machines



' THEAD CONTROL MECHANISM FOR SEWING MCHINES '7 Sheets-Sheet` l Filed Dec.' 9, 1940 Feb. 5, 1946. -v. cHRlsTENsEN r-:TAL'

THREAD CONTROL MECHANISM FOR SEWIG MACH-INES Filed Dec. 9, 1940 7 Sheets-Sheet 2 I. I n ll l wil Feb. 5, 1946. N. cHRlsTENsEN ET Au 2,394,355

THREAD .CONTROL MECHANISM FOR SEWING MACHINES W1 TNESSES; lNl/ENroRs;

' Feb. 5, 3946. N. v. cHRls'TENsEN 'ET AL THREAD CONTROL MECHANISM FO-R SEWING MACHINES Filed Dec. 9, 1940 7 Sheets-Sheet 4 7 Sheets-Sheet BN Ell/lll.,

m A TTORNE YS.

Feb. 5, 1946. N. v. cHRlsTENsEN ETAI.

THREAD CONTROL MECHANISM FOR SEWING MACHINES Filed Dec. 9, 1940 Feb.\5, 1946. N. v.HR|sTNsEN ETAL 2,394,355

THREAD CONTROL MECHANISM FOR SEWING MACHINES A Filed Dec. 9, 1940 '7 sheets-sheet e ATTORNEYS.

Feb. 5, 1946. N. v. cHRlsTx-:NSEN ETAL -2,394,365

THREAD CONTROL MECHANISM FORA SEWING MACHINES y I Filed Deo. 9, 1940 7 Sheets-Sheet 7 INVENTORS:

BY y QZ i ATTORNYS.

been experienced with entanglement and 'wind' Patented Feb. 5, 1,946

PATENT OFFICE f THREA) CONTROL MECHANISM FOR SEWING MACHINES Numan V. Christensen, Chicago, Harold J. Le Vesconte, Western Springs, and Albert M. Schweda, Chicago, Ill., assig'nors to Union Spe cial Machine Company, ration of Illinois Chicago, Ill., a 601130 Application December 9, 1940, serial No. 369,24s`

siciaims. A(ci. 11e-24s) v 'I'his invention relates to thread control mechanism for sewingmachines, and has reference more particularly to rotary mechanism for controlling the needle thread of lock stitch sewing machines. l With rotary needle thread take-ups as here tofore ordinarily constructed, much diillculty has ing up ofthe threads, in the event of breakage,

either upon the take-up rotors or upon their suplo' porting or actuating shafts, lthe correction for which was not only tedious but consumed a great amount of time. A further drawback of the usual forms of takeups is that their action upon thin threads or cheap threads of low tensile il strength is too severe, with resultant causation of frequent ruptures, particularly when the sewing machines are run at the high speeds now considered essential in various lines of manu. facture.

The chief aim of our invention is to overcome the vforegoing drawbacks. .This objective we realized, as hereinafter more fully disclosed, through provision of a simple and reliable takeup mechanism wherein a pair of guard plates interiorly of the path or orbit of a revolving threadpulling element having a uniform angular velocity, coniine the thread. so that, in the event of its rupture, it cannot possibly become entangled with or wound upon said element or the spindle 3 or shaft which carries it; and wherein a pair of stationary guides external to said path or orbit are so disposed relative to each other and a fixed thread detaining element extending crosswise between the plates, as to make possible the use of a rotor of comparatively small diameter and correspondingly small inertia to facilitate quick starting and stopping of the sewing machine, and moreover, as to determine taking-up ofthe thread in considerably less than a semif-rotation of the take-up element compensatively lwith the release of the thread as the latter passes about the non-rotating bobbin holder of the rotary hook of the sewing machine to the end that strain on the thread is reduced to a minimum. The control mechanism of our invention is thus especially adapted for use with sewing machines whereof the rotary hooks make several revolutions incident to each stitch-forming cycle.

Another object of our invention is to attain 50 these advantages in a take-up in which the shaft of the rotor is driven from the needle actuating shaft of-the sewing machine, but so positioned in the needle head as tomake 'possible the use of bearings for the `needle bar above and below the mechanism.

region of its connection to the actuating means therefor.

Other objects and attendant advantages will appear from the'following detailed description of the attached drawings, wherein Fig. 1 is a view, partly in side elevation and partly in longitudinal section, of a. lock stitchl sewing machine conveniently embodying the needle thread controlling mechanism of our invention.

Fig. 2 is a fragmentary view corresponding to Fig. 1, drawn to a larger scale and showing the needle head and a portion of the underlying work y support of the machine in section.

Fig. 3 shows the left hand end elevation of the machine 'with a portion of the work support broken away and in section,

Fig. 3a is a view like Fig. 3 with the take-u slightly further advanced in its rotation.

Fig. 4 is a fragmentary view of the needle head of the machine with the cover thereof removed to expose the parts at the interior.

Fig. 5 is a fragmentary detail view in plan looking as indicated by the angled arrows V-V in Fig. 3.

Figs. 6, 7, 8, and 9 are views like Figs. 3 and 3a, but showing the rotary take-up in diierent successive positions during the stitch-forming cycle.

Fig. 10 is a fragmentary view corresponding to Fig. 8 and drawn to a larger scale.

Fig. 11 is a fragmentary sectional view taken as indicated by the angled arrows XI--XI in Fig. 5.

Fig. 12 is a perspective view of a bearing block forming one of the component parts of the needle thread control. l

Figs. 13 and 14 are detailed sectional views `taken as indicated respectively by the angled arrows XIII--XIII and XIV-XIV. in Fig. 3, and showing the thread tensioning means of the machine which assists in controlling the needle thread. v

Figs. 15, 16, 17, and 18 are perspective views of other component parts of the thread control Fig. 19 is an exploded view of the parts which constitute the thread tensioning means shown in detail in Figs. 13 and 14.

Figs. 20 and 21 are perspective views of upper and lower plate components which together form the needle head cover of the machine.

Figs. 22, 23 and 24 are views generally like Figs.

dividual component parts of the alternative construction.

The lock stitch sewing machine, which we have chosen for convenience of exemplfying our improved needle thread control mechanism in Figs. 1-10, is shown as having a base I whereof the horizontaltop plate 2 constitutes the work support. Integrally formed with the work support 2 at one end, is a. hollow standard 3 which sustains a hollow overhanging arm 4, the latter terminating at its free end in a head 5 whereof the cover plate consists of separately removable upper and lower sections 6, -1 which are secured by screws 8, 9 respectively. The needle III of the machine is xed in the lower end of a, vertical bar II guided for up and down movement in bearings i2, I3 respectively, see Figs. 2, 4 and 11, at the top and bottom of the needle head 5. Through a pitman I4, the needle bar II is coupled with a cuunterbaianced actuating crank l5 at the left hand end of a horizontal shaft I6 which extends through the overhanging arm 4 and is journaled se. does not form parto: the present invention in fore and aft bearing sleeves I1 and I8, respectively. set into a. cross partition I9 at the needle head 5 and in the outer wall 20 of the standard 3, where said shaft protrudes and carries a combined hand and beit wheel 2 I.

Arranged to cooperate with the needle I0 in stitch formation is a rotary hook 22 of well-known construction, with a rotating component 23 baving at its periphery a beak 24 for seizing loops L of the needle thread T and a non-rotating component or bobbin case holder 23:1: from which the bobbin thread B emerges at one side, see Fig. 3L The rotating component 23 of the hook 22 is secured by set screws 25 to the outer end of a horilontal shaft 26 which is journaled in a fixed bearing sleeve 21 beneath the work support 2. At its right hand end, the shaft 26 extends into n. small housing 28 whereof the side walls are integrally formed with and depend from the work support 2, and whereof the bottom 29 is removably secured by screws 30. Fixed on the hookchaft 26 within the housing 28 is a spur gear 3i which meshes with a larger spur gear 32 on another horizontal shaft 33 which is likewise rotatably supported beneath the work support 2, the ratio of said gears being in the order of one Vto two. As shown in Fig. 1, the shaft 33 extends rearward through a bearing sleeve 35 into a downward prolongation 36 of the standard 3 which lat ter is closed at the bottom by a removable plate 31 secured by screws 38. Within the standard 3, the shaft 33 is operatively connected to the upper or needle-actuating shaft I6 through a train of spur gears 39, 40 and 4I, the ratio of which is such that said shafts are rotated in unison and in the same direction. The housing 28 and the pendant portion 36 of the standard 3 are filled with oil to the levels indicated in Fig. l, for the automatic lubrication of the gears within them. The non-rotating component 23:1.' of the hook 22 has a recess 43 at the top of its face flange en- Saeed by a lug on a detaining finger 45 secured to the underside of the work support 2, see Fig. 3,

and is thereby prevented from rotation with the rotating component 23. Incident to being sewed in the machine, the fabric F being sewed is prosressed transversely of the -work support 2 by means of a four motion feed dog 46 whereof the it need not be further referred to herein. The toothed projections of the feed dog 46 operate upwardly through slots in a throat plate '48 set into the top ofthe work support 2 and react upona presser foot 49 which is pivoted to a shank member 50 at the lower end of a vertical presser bar 6I, and which, as ordinarily, extends upward into the needle head 5 for confinement to vertical reciprocation. 'Within the needle head 5 the bar 5I is surrounded by a helicalA spring 52 which tends to maintain the presser foot 49 yieldingly in contact with the top surface of the work progressed in the machine by the feed dog 46 in the usual manner, said spring pressing downward upon a collar 53 affixed to said bar. The presser bar 5I is held against rotating through engagement of a lateral projection 54 on the collar 53 within a vertical guide slot 55 at' one side of the needle head 5. Slidingly mounted on the presser bar 5I beneath the collar 53 with provision normally of a clearance between it and the latter` collar as shown, is a second collar 56 which likewise has a'. lateral projection 51 extending out through the vertical guide slot 55 in the needle head. The collar 56 also has an inward projection 58 (Figs. 2 and 14) which, through a link 59, is coupled with a lever 88 which is fulcrumed to rock about a screw stud 6I at the back of the needle head 5. By means of a drop link 62 (Fig. 3) the lever 60 may be connected to a suitable actuating knee press or foot treadle (not illustrated). Through the means just described, the presser foot 49 can be elevated when desired for convenience of initially inserting the work beneath same. In addition, the machine is provided with a finger latch 63 which is pivoted on a screw 65 and which has a cam portion l61 within the vertical slot 55 in the rear of the needle head 5 (see Fig. 4) bearing against the bottom of the projection 51 on the collar 56. Thus when the latch 63 is swung upward from the position shown in Fig. 3, the presser foot 49 is raised clear of the mechanism with which our invention is more especially concerned. As shown, this mechanism includes a needle thread take-up rotor in the form of a disc 18 at the outer end of a short horizontal shaft or spindle 1I which extends into the needle head 5 and which is journaled in a bearing block 12. In the present instance, the bearing block 12 is made as a separate part and is secured within the top of the needle head 5 by a pair of screws 13. Amxed to the inner end of the spindle 1I is a spur gear pinion 15 which meshes with a drive pinion 16 on the needle actuating shaft I6 in the interval between the crank member I5 and the bearing I1, the ratio of the gears being such that the disc 16 is rotated in unison with said needle actuating shaft but in the opposite direction. If

desired, the bearing 12 may be integrally formed with the frame'of the machine, and, as shown, has axially-aligned bosses at opposite ends thereof, the boss at the left hand end extending outward through a clearance opening 'I4 in the upper section 6 of the needle head coverplate. Access o may be had tothe needle operating mechanism actuating mechanism is generally designated by 'f simply by removing the lower head cover section 1 only. Associated with the disc 18 and positioned immediately forward thereof, is a pair of substantially-circular stationary coaxial guard plates 11 and 13 which are laterally spaced to provide a 80 which constitutes the needle thread pulling ele- .on the threaded 4outer end of the stud` 98 is a tapered helical spring |08 whereby the inner tension disc |02 is yieldingly maintained in frictional I contactwith the outer end of-the mounting comment of the take-up, overhangs, i. e. extends beyond the outer end of the spindle or shaft 1|, and duringthe taking-up of thel needle thread in a manner later on explained, travels about the peripheries of the guard plates 11 and 18.' Inward of the lug 80 and in radial alignment therewith (see Fig. 15) the disc 10 is formed with an opening for the purposes. of dynamic balance. For the sake of greater compactness of the take-up, the disc is recessed at the front, see Figs. 2, 5 and to accommodate the guard plate 11, which, at

the lower part of its periphery has a cam edge A 8| of substantially-90 extent operative upon the needlethread T in a manner also hereinafter explained. The guard plate 11 is secured to the frontal guard plate 18 at a point belowthe axis of the take-up disc 10 by a small segmental connectlng lug 82 adjacent the periphery of the two plates, which lug operates as a thread detaining element Within the path or orbit of the lug 80` on said disc and which may be integrally formed with the guard plate 18 as shown in Fig. 1'1. The frontal guard plate 18 is truncated or cutaway at the bottom along an inclined line as at 83, and provided with a lateral shank 85, which, as shown in Figs. 5 and 17, is offset at 86 to clear the projection 80 on the disc 10 and secured to the needle head 5 by a. pair of screws shown at 81 in Fig. 3.

Enroute from a suitable source of supply, not illustrated, the needle thread T rst passes through a fixed guide 88 which is separately illustrated in perspective in Fig. 18, said guide hav- .ing three spaced vertically-arranged apertures for passage of the thread in the manner shown in Figs. 3l and 6-9, and beingformed with a lateral lug 89 for attachment to the needle head 5 by the lower of the two screws 81. From the guide 88 the needle thread T passes to a tension device 90.

As shown in detail in Figs. 13, 14 and 19, the tension device 90 includes a mounting component 9 I with a tubular body from which extends laterally intermediate its ends, a sectoral flange 92 having anarcuate slot 93 concentric with the body axis. The rear end of the body of the mounting component 9| passes with a snug fit, see Figs. 13 and 14, into an aperture 94 in the lower section 1 of the needle head cover, and saidmounting component is secured, with capacity for rotative adjustment, by a cap screw95 whereof the shank passes inwardly intosaid cover section. The tension device 90 further includes a tubular stud com` ponent 96 (Fig. 19) whereof the inner end portion has a circumferential 'groove 91 which is engaged by a set screw 98 (Figs. 13 and 14) threaded laterally into the body of the mounting 9|. Immediately outward of its rear end portion, the stud 98 has a diametrically-reduced smooth cylindric intermediate portion 99, and beyond the latter, a threaded outer end portion |00 with a diametral slot |8| which extends longitudinally inward to a lpolnt within the confines of said intermediate portion. Freely rotatable on the intermediate portion 99 of the stud 98 is a pair of opposed tension discs |02 and |98 between which the needle thread T is adapted to reeve; and bearing against the outer disc |03 is a dished friction washer |05 with a diametral cross bar |08 engaged in the slot |0| of said stud. In compression between the friction washer |05 and an adjustable abutment nut |01 bore in the body of the mounting component 9| is enlarged as atJ |0 for reception of a helical spring which surrounds the inner portion of the stud 98. At the inner end of the spring the wire of the latter is bent inwardly as at ||2 for anchorage in a radial socket hole ||3 in the stud 99, while the outer end of. the spring wire is extended at a tangent and formed with a rounded loop terminal as at ||4 for service as a yielding check nger to act upon the needle thread T in a manner presently explained. The check nger 4 passes outward through a segmental notch I5 in the outer edge of the body of the mounting component `9| by which its motion is limited, and normally bears against the shoulder ||8 of said notch as shown in Fig. 14. Accordingly, the tension of the spring check nnger ||4 can be regulated upon loosening the set screw 98 androtatively adjusting the stud 98 in the mounting component 9|. On the other hand, by rotative adjustment of the mounting component 9|A and incidental shifting of the stop shoulder as permitted by the clamp screw 95, theupper limitof movement of the check -nger ||4 may be varied as desired or required to suit the action of the take-updisc 10. Freely slideable endwise in the bore of the ,stud 98 is a round-ended pin- ||1 whereof one end is adapted to engage the cross bar |05 of the friction washer'l05 and the other end to be engaged by a sloping cam surface 8 on the collar 58 which isl slidable on the presser bar 5|, see Fig. 14. Thus as the presser bar 5| is lifted to elevate the presser'foot 49, the ypin ||1 is thrust outward to move the friction washer |05 away from the tension-discs |03 and thereby release the tension on the needle thread T.

lUpon leaving the tension device 90, the needle thread T passes under aohooked regulating guide |20 which is located below the axis of the take-up disc 10 beyond'the guardy plates 11, 18 and the path or orbit of the lug on said disc and in a vertical plane containing the axis of the needle I0. As shown, the guide |20 has a shank which extends inward through a vertical slot |2| in the lower section 1 of the' needle head cover and is secured in a receiving bore in the collar 53 on the Apresser bar 5| by means of a set screw |22, see Figs. 2, 4 and 14. From the guide |20, the needle thread T passes upward between the guard plates ,11, 18 and over the segmental lug 82 as shown in Figs. 2 and 3,

- then laterally to a stationary guide |23 likewise beyond the path or orbit of the lug 80 on the take-up disc 10. As shown, the guide |23 is adjustably secured by a screw |24 to a-lateral extension |25 of the upper needle head cover Asection 18 below the axis of the rotor. and from thence the thread next passes downwardly to a guide |28 ad'justably secured by a screw |21 to the lower needle head cover section 1 at the bottom, and iinally to the eye of the needle. It is to be especially noted from Fig. 3a that the thread detaining lug 82 lies substantially in a radial line a--c extending from the axis of the take-up disc 10 to the eye'of the guide |23 and that the guide |20 lies in a radial line a-b at an-angle A substantially less than from the line a-c.

'me operation or the thread cbntrci'inechanism with the disc 'l0 revolving. at half the spe'ed of the rotary hook 22, but in the same direction. is as follows: In Fig. 3, a stitch forming cycle is being initiated with the beak 24 of the rotary hook 22 about to enter the stitch loop L of the thread T thrown out by the needle as the latter begins its ascent, the take-up lug 80 on the disc 'I0 having already entered the large supply loop L' defined jointly by the guides |20 and |23 and held from dropping from between the guide plates 18 and 13 by the detaining element 82. Such entry of the take-up lug 80 is made possible through outward displacement of the ascending limb of the thread supply loop L' by the defiecting cam segment 8| on the plate l1 to permit passage of said lug behind said limb as shown in Fig. 3a. During continued rotation of the hook 22, the needle threadloop L is carried downwardly about the` non-rotating component 23:1: by the action of the beak 24 in the usual way, with attendant absorption of the slack provided by the supply loopL' as shown in Fig. 6. In Fig. 7 the needle thread stitch loop L has ljust passed about the lowest point of the non-rotating hook component 23:1: after having robbed the supply loop L substantially of its slack, and said loop has just been engaged by the lug 80 on the take-up disc 10. In Fig. 8, the disc 1| is somewhat further advanced in its rotation, and has taken up most of the excess in the needle thread loop L which now completely envelops the bobbin thread B as more clearly shown in Fig. l0. Alter this the take-up' action continues until its culmination in Fig. 9 when the take-up lug 80 reaches a position ln a radial line R-R passing through the axis of the disc 'I0 and bisecting the angle formed in the contracted needle thread supply loop` L' as a consequence of the allocation of the guides |20 and |23 as shown. The setting of the stitch is cushioned bythe action of the check nger ||4 as a length of thread sufiicient for the next stitch is drawn oil by the advance of the fabric F by the feed dog 46. From the time of initial engagement of the lug 80 with the portion of the thread T which extends between the loop detaining element 82 and the guide eye |23 in Fig. 6

to the point of complete take-up in Fig. 9, the

disc moves substantially through an arc of 145 degrees. The take-up action is thus completed well within the period available for that action, which period begins when the needle thread stitch loop L passes the lowermost point of the non-rotating component 23a: of the hook 22 and which ends with entry of the needle into the fabric F in the formation of the succeeding stitch. From Fig. 9 it will be apparent that suilicient time is allowed for this action even if the fabric being sewed is of extreme thickness. The foregoing timing is made possible through location of the detaining element 82, the guides |20, |23 and the cam segment 0| on the guide plate 'I1 relative to each other and to the path .or orbit of the lug on the disc 10. In this connection it is also important to note that the diameter of the disc 10 is such that the needle thread is taken up compensatively with release thereof by the rotary hook as the latter completes its rotation from the position in which it is shown in Fig. through the position of Fig. 8

to that shown in'Fg. 9. The proper functioning theienion Ilandthecheckllgel' Illbothof which can be accurately regulated to suit the particular thread being used through the hereinbefore described provisions made for their adjustment. It is, furthermore, to be noted that Vby disposing the disc spindle 1| to one side of the needle actuating shaft and driving it from the latter through the spur gears 'l5 and 16, it is possible to employ a full length needle bar with a guide bearing therefor at the top of the needle head. Attention is especially directed to the fact that at the time of stitch setting in Fig. 9, the lug 00 on the disc 'I0 occupies a position in its orbit directly above the regulating guide element |20 so that the segment of the thread extending between said lug and said element is substantially vertical. It therefore follows from this that the amount of thread given up to the take-up will be in direct proportion to variations in the thickness of the material being sewed in the machine and by virtue of the mounting of the regulating guide element |20 on the presser bar 5| in the vertical line of the needle axis.

In the alternative embodiment of our invention illustrated in Figs. 22-27, the take-up disc 10a has a forwardly-extending circumferential iiange |30 with an annular groove I3| and radiallyaligned needle thread-engaging lugs a respectively at opposite sides of the groove. Cooperative with the disc 10a at one side of the top of the latter is stripper element |32 which has a tapered iinger |33 extending into the groove 3|. As shown in Figs. 23 and 26, the attaching projection |35 of the stripper is provided with a transverse slot |35 for passage of the shank of a securing clamp screw |36 which engages into an upward projection |31 on the upper needle head cover section 6a. As a consequence of this construction, the stripper |32 can be adjusted circumferentially of the take-up disc 10a within the range of the slot |35. In all other respects, the construction of the modiication is identical with that of the mst-described embodiment of our invention. Accordingly, in order to preclude the necessity for repetitive description, all correspending parts in the modification are identiiied by the same reference characters previously employed. Incident to the operation of the modic'ation, the needle thread T, after having been taken up to the proper extent, is stripped from the lugs 00a on the disc |0a by the inclined outer edge of the stripper finger |33 in a manner which will be readily understood from Fig. 23, the cycle of operation being otherwise the same as in the first described embodiment. Obviously by shifting the position of the stripper |32 circumferenmachine for use of needle threads of different.

kinds or gauges for proper coaction to the take-up with the rotary hook.

From the foregoing it will be seen that both forms of our improved thread control mechanism are simple in construction, and can be depended -upon for reliability in operation. In each case, the guard plates definitely confine the thread. and in the event of rupture prevent it from becoming entangled with or wolmd upon either the take-up disc or the shaft therefor. In each instance moreover, the rotor is of comparatively small diameter and hence has little inertia. Ac-

accuses cordingly it cuers negligible resistance to quick starting and stopping of the machine.

Having thus described our invention, we claim: l

1. Needle thread control means for a lock stitch sewing machine having a rotary hook with a rtating loop seizing component and a non-rotating bobbin thread housing component within the rotating component. said thread control means being disposed above the hook and including a pair oi vertically arranged guard plates between which the thread passes enroute to the needle; a take-up element which revolves about the peripheries of the guard plates; a pair of thread guides exteriorly of the guard plates; and a loon` stop extending crosswise ofthefplates adjacent their peripheries. said guides and stop being all disposed below the rotative axis of the take-up claim l including means whereby the take-up element is revolved at half the speed of the rotary hook; wherein the thread g'ruides are so spaced that the taking up of the thread is accomplshed in less than a semi-revolution of the takeup element about the guard plates; and wherein a stationary means laterally deiiects one limb of the loop so that the take-up element may enter it during each of its rotations, said deflecting means being also |below the rotative axis of the element and so located with respect to the guides as to determine taking up of the thread during less than a semi-rotation of the take-up element about said guard plates. I

4. Needle thread control means for a sewing machine having a presser foot and a supporting bar therefor, said thread control means comprising a single revolving thread engaging takeup element; a pair of guides for directing the ,thread respectively into and out of the path of the take-up element, one of said guides bein-g stationary and the other affixed to the presser bar for movement therewith; and means adjacent the path of the take-up element intermediate the guides for engaging the thread and predetermining the point o'f initial engagement of the thread by said take-up element during each stitch forming cycle offthe machine.

5. Thread control mechanism for sewing machines and the like, comprising a pair of spaced stationary guard plates between which the thread passes en route to a stitch forming instrumentality of the machine; means for deiining and retaining a supply loop of. the thread between the guard plates; and a take-up element moving in 'an orbit around the peripheries of the guard platesl and adapted to engage the supply .loop during each rotation, said take-up element being in the form of a laterally projecting lug on a revolving disc alongside of one of the two guard plates, and said disc having its face recessed to accommodate such guard plate.

'6. Thread control mechanism for sewing machines and the like, comprising a pair of spaced stationary guard plates between which the thread passes en route to a thread manipulating instruretaining a supply loop of thethread between the guard plates; a take-up element revolving about the peripheries of the guard plates; and means in the form of a segmental cam projection on one of the guard plates for laterally deiiecting one limb of the supply loop to permit the element to enter` the loop during each rotation.

7. Thread control mechanism for sewing machines and the like, comprising a pair of spaced stationary guard plates between which the thread passes en route to a thread manipulating instrumentality'of the machine; a take-up element rev volving about the peripheries of said guard plates; means for dening and retaining a supply loop of the thread between the guard plates including a pair of thread guides externally of said l plates, and a loop stop which extends crosswise of said plates adjacent their peripheries, said thread guides and loop stop being all disposed to one side of the rotative axis of the take-up element; and means for laterally deiiecting one limb of the supply loop to permit entry of said element into the loop during each rotation, said defiecting means being in the form of a segmental cam projection on one of the guard plates located at the same side of the rotative axis of the take-up element as the thread guides and the loop stop.

8. Thread control :mechanism for sewing machines and the like, comprising a pair of spaced stationary, guard plates between which the thread passes en route to a'thread manipulating instrumentality of the machine; means for definingV and retaining a supply loop of thel thread between adapted to engage the supply loop during 'each rotation; and stationary stripper means adjustable peripherally of the guard plates for dis-v lodging the loop from the take-up element at the completion of each take-up cycle.

9. Thread control mechanism for sewing ma- Y chines and the like, comprising a. pair of spaced lstationary guard plates between which the thread passes en route to a thread manipulating instrumentality of the machine; means for defining andfretaininga supply loop ofv the thread between the guard plates; a take-up element revolving about the peripheries of the guard plates and adapted to engage the supply loop during each rotation, said take-up element being in the form of a laterally projecting lug o n a revolving disc alongside one of the guard plates; and stationary stripper means in the'form of a ringer which projects into an annular groove in the face of the disc for dlslodging the loop from the take-up lelement at the completion of each take-up cycle.

determining the point of engagement thereof ulating element.

ll. Thread control mechanism for sewing'machines and the like, comprising a take-up elementality of the machine: means for dening and ment which moves in an orbit in a vertical plane of stitch settingabove the point of stitch formation in the machine to measure a deilnite length of thread in excess of the amount required for each stitch and to take up such excess to set the stitch at the end of each stitch forming cycle; and a regulating element'actuated by changes in the thickness of the material being sewed to compensatively regulate the amount of thread being measured each time. said regulating -element being so disposed relative to the orbit of the thread take-up element that the latter is substantially in a vertical line with said regulating element and the point of stitch formation at the time 12. In a sewing machine having a needle and a presser foot, thread control mechanism comprising a take-up element which moves in an orbit in a vertical plane above the point of stitch formation in the machine to measure a denlte length `of thread in excess of the amount required for each stitch and to take up such excess to set the stitch at the end of each stitch forming cycle; and a regulating element connected to the presser foot for actuation thereby incident to changes in the thickness of the material being sewed to compensatively regulate the amount of thread measured, said regulating element being so disposed relative to the orbit of the thread take-up element that the latter is substantially in a vertical line with said regulating means and the point of stitch formation at the time of stitch setting.

13. In a sewing machine having a vertically reciprocating needle. thread control mechanism comprising a take-up element which moves in an orbit in a vertical plane above the point of stitch formation in the machine to measure a deilnite length of thread in excess of the amount required for each stitch and to take up such excess to set the stitch at the end of each stitch forming cycle;

" and a regulating element in line with the axis of the needle and actuated by changes in the thickness of the material being sewed to compensatively regulate the amount of thread measured, said regulating element being so disposed relative to the orbit of the take-up element that the latter is substantially in a vertical line with said regulating element and the point of stitch formation at the time of stitch setting.

14.- Thread control mechanism for sewing machines and the like. comprising a thread engaging take-up element which moves in an orbit in a vertical plane above the point of stitch formation in the machine to measure a definite length of 'thread in excess of the amount required for each stitch and to take up the excess to set the stitch at the end of each stitch forming cycle; and a thread guide by which the thread is directed into the orbit of` the take-up element actuated by changes in the thickness of the material being sewed to compensatively regulate the amount of thread measured each time, said guide being so disposed relative to the orbit of said take-up elementthat the latter is substantially in a vertical line with the guide and the point of stitch formation at thetime of stitch setting.

15. In a sewing machine having a vertically re- .ciprocating needle, thread control.mechanism comprising a take-up element which moves in an orbit in a vertical plane above thepoint of stitch formation in the machine tovmeasure a denite length of the thread in excess of the amount required for each stitch and to take up such excess to set the stitch at the end of each stitch forming cycle; a thread tension through which thread passes en route from a source of supply; a thread guide which receives the thread from the tension and directs the thread into the orbit of the takeup element; and means for actuating the thread guide in accordance with changes in the thickness of the material being sewed to compensatively regulate the amount of thread measured each time, the guide being so disposed relative to the orbit ofV the take-up element that the latter is substantially in a vertical line with said guide and the point of stitch formation at the time of stitch setting. Y

16. Needle thread control mechanism for a sewing machine having a work support. comprising a thread engaging take-up element disposed above said work support for movement in an orbital zone of operation; a vertically movable thread guldedisposed between said zone and said work support for directing the thread into said zone:a second thread guide disposed laterally and externally of said zone for determining the point of exit of the thread from said zone en route to stitch forming instrumentalities associated with said work support; and thread detaining means positioned intermediate said thread guides for engagement by the threadand operative to determine the point of initial engagement of said thread by said take-up element incident to the disposed between said zone and said work support for directing the thread into said zone; a second thread guide disposed laterally and externally of said zone for determining the point of exit of the thread from said zone en route to stitch forming instrumentalities associated with said work sup- 40 port; and thread detaining means positioned intermediate said thread guides within the area surrounded by said zone and arranged to be engaged by the thread to determine the point of initial engagement of said threadby said take-up element incident to the'formation of a stitch.

18. Needle thread control mechanism for a sewing machine having a work support, comprising a thread engaging take-up element disposed above said work support for movement in an orbital zone of operation; a vertically movable thread guide disposed between said zone and said work support for directing the thread into said zone; a second thread guide laterally and externally of said zone adapted to determine the point of exit of the thread from said zone en route to stitch forming instrumentalitles `associated with said work support; thread detaining means intermediate said thread guides arranged to be engaged by the thread to determine `the point of initial engagement of said thread by said take-up element incident to the formation of a stitch; Yand means within said zone for restraining the thread against excessive movement transverse to its path of travel during the action of said take-up element.

19. Needle thread control mechanism for a sewing machine having a work support. comprising a thread engaging take-up element disposed above said work support for movement in an orbital zone of operation; a vertically movable thread guide disposed between said zone andsaid work support for directing the thread into said zone; a second thread guide laterally and externally of said zone adapted to determine the point of exit of the thread fromsaid zone enroute to stitch forming instrumentalities associated with said work support; thread detaining means intermediate said thread guides and arranged to be engaged by the thread to determine the point of initial engagement of said thread by said take-'up element incident to the formation of a stitch; and a pair oiv spaced guard elements positioned within said zone for restraining the thread against excessive movement transverse to its path of travel during the action of said take-up element.

20. Needle thread control mechanism for a sewing machinehaving a work support and stitch forming nstrumentalities associated with said work support, comprising a take-up element arranged to move in a circular orbit above said work support, said element being spaced radially from and overhangingthe end of a rotatable supporting and actuating shaft; a vertically movable thread Aguide disposed between said work support and said orbit for/directing the thread en route from the supply across and withinv said orbit; a second thread guide laterally of and external to said orbit for directing the thread out of said orbit en route to said stitch forming instrumentalities; and a thread detaining means adjacentsaid orbit and intermediate said guides, arranged .to position the thread for initial engagement by said take-up element incidentto the'formation of a stitch. I 2l` Needle vthread control mechanism for sewing machine having a work support and stitch forming instrumentalities associated with said work support, comprising a take-up element arranged to move in/a circular orbit above said work support, said element being spaced radially bit and intermediatesaid guides arranged to po-` sition the thread for initial engagement by said take-up element incident to the formation of a stitch; and a pair of spaced guard elements Within the orbit of the take-up element for restraining the thread against excessive movement laterally of its path of travel while said thread vis being acted upon by said take-up element.

22. Needle thread control mechanism for a sewing machine having a work support and stitch forming nstrumentalities associated with said work support, comprising a take-up element arranged to move in a circular orbit above said work support, said element being spaced radially from and overhanging the end of a rotatable supporting and actuating shaft; a vertically movable thread guide disposed "between said work support and said orbit for directing the thread, en route from a supply, across and within said orbit; a second thread guide laterally of and ex' ternal to said orbit for directing the thread out of said orbit en route to said stitch forming instrumentalities; thread detaining means adjacent said orbit and intermediate said guides, arranged to position the thread for initial engagement by said take-up element incident to the formation of a stitch; and a thread tension device adapted to engage said thread in advance of its engagement by said first-named thread guide.

23. Needle thread control mechanism for a sewing machine having a work support and stitch forming instrumentalities associated with said work support. comprising a take-up element which is arranged to move in a circular orbit above said work support, said element being spaced radially from and overhanging the end of a rotatable supporting and actuating shaft; a vertically movable thread guide disposed between said work support and said orbit for directing the thread, en route from the supply, across and within said orbit; a second thread guide disposed laterally of and external to said orbit for directing the thread out ,of saidorbit en route to said stitch forming nstrumentalities; and a thread detaining element positioned between the orbit of said take-up element and the axis of said rotatable shaft and lying approximately in a radial line which extends through the axis of said shaft said zone and said work support for directing the thread into said zone; a second thread guide disposed laterally and externally of said zone for determining the point of exit of the thread from said zone en route'to stitch forming instrumenta'lities associated with said Work support, said second thread guide lying in a radial line which extends through the axis of said zone at an angle of less than ninety degrees from a radialline containing said iirst-named thread guide; and stationary thread detaining means within said zone adapted to be engaged by said thread, and thereby to determine the point of initial engagement of said thread by said takeup element.

25. In asewing machine, a thread take-up device comprising, adjacent thread-engaging members rotatable in a common plane about acommon axis spaced a substantial distance from said members, said members having leading and trailing edges, said members being spaced one from the other on va common radius and providing therebetween an arcuate thread-removing element clearance slot concentric with the paths of ro\ l means, and a thread-removing element extending.

transversely of said plane of rotation of said takeup means and disposed to traverse said passage in the rotation of said means.

27. In a sewing machine, a thread take-up de- Y vice comprising, a disk rotatable about a fixed axis, thread-engaging means extending from a side face of said disk with all portions thereof eccentric to said axis and adapted to effect a take-up acticnon a thread by engaging and shifting a bight of said vthread in a plane parallel to the face of said disk, said means being provided in the end face thereof opposite to said disk with a thread-removing element clearance passage, and a thread-removing element extending transversely of said side face of the disk and disposed to traverse said passage in the rotation of said means.

28. In a sewing machine, a thread take-up device comprising, a disk rotatable about a xed axis, thread-engaging means extending from a side face of said disk with all portions thereof eccentric to said axis and adapted to effect a take-up action on a thread by engaging and shifting a bght of said thread in a plane parallel to the face of said disk, said means being provided in the end face thereof opposite to said disk with an arcuate thread-removing element clearance passage having said axis as its center of curvature, and a stationary thread-removing element disposed to traverse said passage in the rotation of said means.

29. In a sewing machine, a rotary thread take- 32. A rotary take-up for the needle thread of a sewing machine having a reciprocatory needle which comprises a disk mounted on the frame of the machine above the point of stitch formation, means for rotating said disk in timed relation with the reciprocations of said needle. a plurality of thread engaging elements projecting laterally abruptly from said disk and so disposed thereon as to be carried in orbital paths incident to the rotation of said disk, means within and without said orbital paths for positioning a needle thread enroute from a source of supply to the point of stitch formation for periodic engagement by said threadengaging elements, said elements being elongated circumferentially of said orbital paths and 'seing spaced along a line radial to said paths to provide adjacent parallel wall portions forming an arcuate clearance passage open at the outer ends of said elements and concentric with said orbital paths, and a stationary thread engaging member in xed relation to said frame, said member including a thread-engaging portion extendvice comprising, a disk rotatable about a xed axis, thread-engaging means extending from a side face of said disk with all portions thereof eccentric to said axis and adapted to eiect a takeup action on a thread by engaging and shifitng a bight of said thread in a plane parallel to the face of said disk, said means being provided in the end face thereof Witha thread-removing element clearance slot extending depthwise transversely of said face of said disk, means complemental to said disk for coniining the thread for engagement by said means, and a thread-removing element disposed to xtraverse said slot in the rotation of said means.

3l. A rotary take-up for the needle thread 'of a sewing machine having a reciprocatory needle which comprises a disk mounted on the needle head and rotated in timed relation with the reciprocation of the needle, means projecting laterally from said disk and carried thereby through an orbital path, all portions of said means being spaced a substantial distance from the axis of rotation of said disk and being arranged to engage the needle thread and shift the same in a plane parallel to the face of the disk to eilect a take-up action thereon upon each revolution of said disk, and means serving to remove thread engaged with said projecting means 'in' cluding an arcuate passage formed in said projecting means concentric with said orbital path and a stationary member projecting into the piane of said projecting means and arranged to traverse said arcuate passage upon each revolution of said disk. i

ing in a direction parallel to the axis of rotation of said disk and so positioned as to traverse said clearance passage incident to the rotation of said take-up elements. I

33. A rotary take-up for the needle thread of a lock stitch sewing machine comprising a rotatable shaft carried by the needle head of the machine, a disk secured to said shaft adjacent the free end of said needle head, means providing a pair of thread engaging elements projectingV laterally from said vdisk and movable in an orbital path incident to the rotation of said disk,

said elements having leading and trailing thread retaining edges and being spaced from each other in aradial direction with respect to said orbital path and providing an arcuate passage between them which is concentric with said orbital path,

40 thread guiding means for leading thread from a source of supply into the zone of action of said elements and from said zone to the point of stitch formation, and a stationary thread engaging member-extending inwardly into the space between the orbits of said elements and arranged to traverse said arcuate passage'.

34. In a take-up fora sewing machine a disk fixed to the end of a rotatable shaft, thread takeup means iixed to the face of said disk comprising a pair of circumferentially elongated, laterally extending thread engaging members provided with leading and trailing thread retaining edges, said members having adjacent faces spaced from each other and concentric with the axis of said shaft forming an arcuate slot extending depthwise parallel to said axis, and stationary means including a member having a free end terminating closely adjacent to the face of said disk and positioned to traverse said arcuate slot incident to the rotation of said disk and shaft, said means serving to remove thread engaged with said takev up means.

NORMAN V. CHRIS'IENSEN. HAROLD J. LE VESCONTE. ALBERT M. SCHWEDA. 

